| By this time, the technology of hyperspectral mineral mapping mainly research on visible - infrared (0.35 ~ 2.5μm). The methods of the mineral mapping have gradually matured, and have formed a more complete methodology. Quantitative inversion of mineral content has also made progress, but it is also facing many new challenges, such as: (1) It relativly lag behind for the mechanization research between the rock and mineral medium surface and light radiation. But it is the basis of precise quantitative remote sensing information extraction of rock and mineral to the capture of the structural information and accurate bidirectional reflectance data. (2)Make the spectral region of hyperspectral mineral mapping and the extraction technology range from the visible - infrared reflection to extend to the mid-infrared (2.5 ~ 25μm) band, set up the whole spectrum mineral identification rules and method, in order to improve the abillity and precision of rock recognition base on remote sensing. However, duing to the thermal infrared remote sensing data acquisition, processing and emissivity data inversion is a great problem, which lead to the research of the information extraction in the middle-infrared band lag.Many types of mineral powder is regarded as the research object. In visible -reflection infrared (0.35～2.5μm) band, multi-angle rock bidirectional reflectance measured in laboratory was the data source. This paper developed the inversion system based on "a constrained nonlinear least squares method" using Matlab and Visual c # language, proposed and established sensitivity analysis and retrieval system in stages based on "prior knowledge". The expert's prior knowledge, Hapke reflectance model and the experimental data were hung together, which realized the sensitivity analysis and optimization inversion of the initial value in all visible light - reflection Infrared(0.35 ~ 2.5μm) bands for the five parameters of Hapke reflectance model (the average single scattering albedo W, before and after the scattering phase function scale factor c, the amplitude of the phase function b, the backscatter experience coefficient B0, the width of the effect after h) .Sensitivity analysis shows that: The contribution of the various parameters of Hapke reflectance model to the bidirectional reflectance is interactive. The multiple parameters involved in inversion is an interaction. The relevance of the sensitivity of inversion parameters is also an important influence factor for parameter inversion accuracy. The average single scattering albedo W, before and after the scattering phase function scale factor , the amplitude of the phase function b have high sensitivity on the set of initial value, the backscatter experience coefficient B0, and the width of the effect after h has less sensitivity on the set of the initial value.The inversion results of the optimum inversion initial value after determining parameters show that: the root mean square error of the inversion results is very small. The bidirectional Reflectance simulated by Hapke reflectance model is almost the same as the raw data. This explained that Hapke reflectance model can simulate the spectrum formation and the variation mechanisms from the physical level. This paper summarized the laws and characteristics of the five parameters based on the target of rock. It plays an important role on understanding the rock and mineral spectral mechanism and the improvement of the quantitative identification about the rock and minerals based on remote sensing.Analyzing and summarizing the IR spectral mechanism and classification of the major minerals in the thermal infrared (2.5 ~ 25μm). The infrared spectra analysis of common minerals showed that silicate, sulfate detection, carbonates, phosphates, oxides, hydroxides and other minerals can be identified in this interval (including non-water rock-forming minerals),. The identification capabilities and precision of remote sensing of rock and minerals can be comprehensively improved. Taking the multi-types middle-thermal infrared spectra measured by the lib as the endmember spectra and mixed spectra, taking identification methods based on spectral similarity algorithm as the technical support, deeply researched and developed the mineral spectral mixed properties, mineral unmixing and the inversion method of mineral content in the thermal infrared (2.5 ~ 25μm ).The above study shows that, it is a useful exploration in the depth and breadth for the existing hyperspectral remote sensing mineral mapping to study the mineral species identification, spectral unmixing, content inversion on the range of thermal infrared and study the bidirectional reflectance characteristics of rock and mineral using Hapke reflectance model. Based on these, comprehensively applying the visible t - reflection infrared remote sensing and thermal infrared spectral to develop the whole spectrum mineral identification rules. Rock and mineral identification is an effective way to improve the accuracy, capability and reliability of rock and mineral identification of remote sensing.
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